/*
 *------------------------------------------------------------------
 * Copyright (c) 2019 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *------------------------------------------------------------------
 */

#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/rand.h>
#include <openssl/sha.h>

#include <vlib/vlib.h>
#include <vnet/plugin/plugin.h>
#include <vnet/crypto/crypto.h>
#include <vpp/app/version.h>

typedef struct
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
  EVP_CIPHER_CTX *evp_cipher_ctx;
  HMAC_CTX *hmac_ctx;
  EVP_MD_CTX *hash_ctx;
#if OPENSSL_VERSION_NUMBER < 0x10100000L
  HMAC_CTX _hmac_ctx;
#endif
} openssl_per_thread_data_t;

static openssl_per_thread_data_t *per_thread_data = 0;

#define foreach_openssl_aes_evp_op                                            \
  _ (cbc, DES_CBC, EVP_des_cbc, 8)                                            \
  _ (cbc, 3DES_CBC, EVP_des_ede3_cbc, 8)                                      \
  _ (cbc, AES_128_CBC, EVP_aes_128_cbc, 16)                                   \
  _ (cbc, AES_192_CBC, EVP_aes_192_cbc, 16)                                   \
  _ (cbc, AES_256_CBC, EVP_aes_256_cbc, 16)                                   \
  _ (gcm, AES_128_GCM, EVP_aes_128_gcm, 8)                                    \
  _ (gcm, AES_192_GCM, EVP_aes_192_gcm, 8)                                    \
  _ (gcm, AES_256_GCM, EVP_aes_256_gcm, 8)                                    \
  _ (cbc, AES_128_CTR, EVP_aes_128_ctr, 8)                                    \
  _ (cbc, AES_192_CTR, EVP_aes_192_ctr, 8)                                    \
  _ (cbc, AES_256_CTR, EVP_aes_256_ctr, 8)

#define foreach_openssl_chacha20_evp_op                                       \
  _ (chacha20_poly1305, CHACHA20_POLY1305, EVP_chacha20_poly1305, 8)

#if OPENSSL_VERSION_NUMBER >= 0x10100000L
#define foreach_openssl_evp_op foreach_openssl_aes_evp_op \
                               foreach_openssl_chacha20_evp_op
#else
#define foreach_openssl_evp_op foreach_openssl_aes_evp_op
#endif

#ifndef EVP_CTRL_AEAD_GET_TAG
#define EVP_CTRL_AEAD_GET_TAG EVP_CTRL_GCM_GET_TAG
#endif

#ifndef EVP_CTRL_AEAD_SET_TAG
#define EVP_CTRL_AEAD_SET_TAG EVP_CTRL_GCM_SET_TAG
#endif

#define foreach_openssl_hash_op                                               \
  _ (SHA1, EVP_sha1)                                                          \
  _ (SHA224, EVP_sha224)                                                      \
  _ (SHA256, EVP_sha256)                                                      \
  _ (SHA384, EVP_sha384)                                                      \
  _ (SHA512, EVP_sha512)

#define foreach_openssl_hmac_op \
  _(MD5, EVP_md5) \
  _(SHA1, EVP_sha1) \
  _(SHA224, EVP_sha224) \
  _(SHA256, EVP_sha256) \
  _(SHA384, EVP_sha384) \
  _(SHA512, EVP_sha512)

static_always_inline u32
openssl_ops_enc_cbc (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		     vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		     const EVP_CIPHER *cipher, const int iv_len)
{
  openssl_per_thread_data_t *ptd = vec_elt_at_index (per_thread_data,
						     vm->thread_index);
  EVP_CIPHER_CTX *ctx = ptd->evp_cipher_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 i, j, curr_len = 0;
  u8 out_buf[VLIB_BUFFER_DEFAULT_DATA_SIZE * 5];

  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];
      vnet_crypto_key_t *key = vnet_crypto_get_key (op->key_index);
      int out_len = 0;

      if (op->flags & VNET_CRYPTO_OP_FLAG_INIT_IV)
	RAND_bytes (op->iv, iv_len);

      EVP_EncryptInit_ex (ctx, cipher, NULL, key->data, op->iv);

      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	EVP_CIPHER_CTX_set_padding (ctx, 0);

      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  u32 offset = 0;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      EVP_EncryptUpdate (ctx, out_buf + offset, &out_len, chp->src,
				 chp->len);
	      curr_len = chp->len;
	      offset += out_len;
	      chp += 1;
	    }
	  if (out_len < curr_len)
	    EVP_EncryptFinal_ex (ctx, out_buf + offset, &out_len);

	  offset = 0;
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      clib_memcpy_fast (chp->dst, out_buf + offset, chp->len);
	      offset += chp->len;
	      chp += 1;
	    }
	}
      else
	{
	  EVP_EncryptUpdate (ctx, op->dst, &out_len, op->src, op->len);
	  if (out_len < op->len)
	    EVP_EncryptFinal_ex (ctx, op->dst + out_len, &out_len);
	}
      op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
    }
  return n_ops;
}

static_always_inline u32
openssl_ops_dec_cbc (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		     vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		     const EVP_CIPHER *cipher, const int iv_len)
{
  openssl_per_thread_data_t *ptd = vec_elt_at_index (per_thread_data,
						     vm->thread_index);
  EVP_CIPHER_CTX *ctx = ptd->evp_cipher_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 i, j, curr_len = 0;
  u8 out_buf[VLIB_BUFFER_DEFAULT_DATA_SIZE * 5];

  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];
      vnet_crypto_key_t *key = vnet_crypto_get_key (op->key_index);
      int out_len = 0;

      EVP_DecryptInit_ex (ctx, cipher, NULL, key->data, op->iv);

      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	EVP_CIPHER_CTX_set_padding (ctx, 0);

      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  u32 offset = 0;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      EVP_DecryptUpdate (ctx, out_buf + offset, &out_len, chp->src,
				 chp->len);
	      curr_len = chp->len;
	      offset += out_len;
	      chp += 1;
	    }
	  if (out_len < curr_len)
	    EVP_DecryptFinal_ex (ctx, out_buf + offset, &out_len);

	  offset = 0;
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      clib_memcpy_fast (chp->dst, out_buf + offset, chp->len);
	      offset += chp->len;
	      chp += 1;
	    }
	}
      else
	{
	  EVP_DecryptUpdate (ctx, op->dst, &out_len, op->src, op->len);
	  if (out_len < op->len)
	    EVP_DecryptFinal_ex (ctx, op->dst + out_len, &out_len);
	}
      op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
    }
  return n_ops;
}

static_always_inline u32
openssl_ops_enc_aead (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		      vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		      const EVP_CIPHER *cipher, int is_gcm, const int iv_len)
{
  openssl_per_thread_data_t *ptd = vec_elt_at_index (per_thread_data,
						     vm->thread_index);
  EVP_CIPHER_CTX *ctx = ptd->evp_cipher_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 i, j;
  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];
      vnet_crypto_key_t *key = vnet_crypto_get_key (op->key_index);
      int len = 0;

      if (op->flags & VNET_CRYPTO_OP_FLAG_INIT_IV)
	RAND_bytes (op->iv, 8);

      EVP_EncryptInit_ex (ctx, cipher, 0, 0, 0);
      if (is_gcm)
	EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_GCM_SET_IVLEN, 12, NULL);
      EVP_EncryptInit_ex (ctx, 0, 0, key->data, op->iv);
      if (op->aad_len)
	EVP_EncryptUpdate (ctx, NULL, &len, op->aad, op->aad_len);
      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      EVP_EncryptUpdate (ctx, chp->dst, &len, chp->src, chp->len);
	      chp += 1;
	    }
	}
      else
	EVP_EncryptUpdate (ctx, op->dst, &len, op->src, op->len);
      EVP_EncryptFinal_ex (ctx, op->dst + len, &len);
      EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_AEAD_GET_TAG, op->tag_len, op->tag);
      op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
    }
  return n_ops;
}

static_always_inline u32
openssl_ops_enc_gcm (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		     vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		     const EVP_CIPHER *cipher, const int iv_len)
{
  return openssl_ops_enc_aead (vm, ops, chunks, n_ops, cipher,
			       /* is_gcm */ 1, iv_len);
}

static_always_inline __clib_unused u32
openssl_ops_enc_chacha20_poly1305 (vlib_main_t *vm, vnet_crypto_op_t *ops[],
				   vnet_crypto_op_chunk_t *chunks, u32 n_ops,
				   const EVP_CIPHER *cipher, const int iv_len)
{
  return openssl_ops_enc_aead (vm, ops, chunks, n_ops, cipher,
			       /* is_gcm */ 0, iv_len);
}

static_always_inline u32
openssl_ops_dec_aead (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		      vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		      const EVP_CIPHER *cipher, int is_gcm, const int iv_len)
{
  openssl_per_thread_data_t *ptd = vec_elt_at_index (per_thread_data,
						     vm->thread_index);
  EVP_CIPHER_CTX *ctx = ptd->evp_cipher_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 i, j, n_fail = 0;
  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];
      vnet_crypto_key_t *key = vnet_crypto_get_key (op->key_index);
      int len = 0;

      EVP_DecryptInit_ex (ctx, cipher, 0, 0, 0);
      if (is_gcm)
	EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_GCM_SET_IVLEN, 12, 0);
      EVP_DecryptInit_ex (ctx, 0, 0, key->data, op->iv);
      if (op->aad_len)
	EVP_DecryptUpdate (ctx, 0, &len, op->aad, op->aad_len);
      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      EVP_DecryptUpdate (ctx, chp->dst, &len, chp->src, chp->len);
	      chp += 1;
	    }
	}
      else
	EVP_DecryptUpdate (ctx, op->dst, &len, op->src, op->len);
      EVP_CIPHER_CTX_ctrl (ctx, EVP_CTRL_AEAD_SET_TAG, op->tag_len, op->tag);

      if (EVP_DecryptFinal_ex (ctx, op->dst + len, &len) > 0)
	op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
      else
	{
	  n_fail++;
	  op->status = VNET_CRYPTO_OP_STATUS_FAIL_BAD_HMAC;
	}
    }
  return n_ops - n_fail;
}

static_always_inline u32
openssl_ops_dec_gcm (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		     vnet_crypto_op_chunk_t *chunks, u32 n_ops,
		     const EVP_CIPHER *cipher, const int iv_len)
{
  return openssl_ops_dec_aead (vm, ops, chunks, n_ops, cipher,
			       /* is_gcm */ 1, iv_len);
}

static_always_inline __clib_unused u32
openssl_ops_dec_chacha20_poly1305 (vlib_main_t *vm, vnet_crypto_op_t *ops[],
				   vnet_crypto_op_chunk_t *chunks, u32 n_ops,
				   const EVP_CIPHER *cipher, const int iv_len)
{
  return openssl_ops_dec_aead (vm, ops, chunks, n_ops, cipher,
			       /* is_gcm */ 0, iv_len);
}

static_always_inline u32
openssl_ops_hash (vlib_main_t *vm, vnet_crypto_op_t *ops[],
		  vnet_crypto_op_chunk_t *chunks, u32 n_ops, const EVP_MD *md)
{
  openssl_per_thread_data_t *ptd =
    vec_elt_at_index (per_thread_data, vm->thread_index);
  EVP_MD_CTX *ctx = ptd->hash_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 md_len, i, j, n_fail = 0;

  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];

      EVP_DigestInit_ex (ctx, md, NULL);
      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      EVP_DigestUpdate (ctx, chp->src, chp->len);
	      chp += 1;
	    }
	}
      else
	EVP_DigestUpdate (ctx, op->src, op->len);

      EVP_DigestFinal_ex (ctx, op->digest, &md_len);
      op->digest_len = md_len;
      op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
    }
  return n_ops - n_fail;
}

static_always_inline u32
openssl_ops_hmac (vlib_main_t * vm, vnet_crypto_op_t * ops[],
		  vnet_crypto_op_chunk_t * chunks, u32 n_ops,
		  const EVP_MD * md)
{
  u8 buffer[64];
  openssl_per_thread_data_t *ptd = vec_elt_at_index (per_thread_data,
						     vm->thread_index);
  HMAC_CTX *ctx = ptd->hmac_ctx;
  vnet_crypto_op_chunk_t *chp;
  u32 i, j, n_fail = 0;
  for (i = 0; i < n_ops; i++)
    {
      vnet_crypto_op_t *op = ops[i];
      vnet_crypto_key_t *key = vnet_crypto_get_key (op->key_index);
      unsigned int out_len = 0;
      size_t sz = op->digest_len ? op->digest_len : EVP_MD_size (md);

      HMAC_Init_ex (ctx, key->data, vec_len (key->data), md, NULL);
      if (op->flags & VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS)
	{
	  chp = chunks + op->chunk_index;
	  for (j = 0; j < op->n_chunks; j++)
	    {
	      HMAC_Update (ctx, chp->src, chp->len);
	      chp += 1;
	    }
	}
      else
	HMAC_Update (ctx, op->src, op->len);
      HMAC_Final (ctx, buffer, &out_len);

      if (op->flags & VNET_CRYPTO_OP_FLAG_HMAC_CHECK)
	{
	  if ((memcmp (op->digest, buffer, sz)))
	    {
	      n_fail++;
	      op->status = VNET_CRYPTO_OP_STATUS_FAIL_BAD_HMAC;
	      continue;
	    }
	}
      else
	clib_memcpy_fast (op->digest, buffer, sz);
      op->status = VNET_CRYPTO_OP_STATUS_COMPLETED;
    }
  return n_ops - n_fail;
}

#define _(m, a, b, iv)                                                        \
  static u32 openssl_ops_enc_##a (vlib_main_t *vm, vnet_crypto_op_t *ops[],   \
				  u32 n_ops)                                  \
  {                                                                           \
    return openssl_ops_enc_##m (vm, ops, 0, n_ops, b (), iv);                 \
  }                                                                           \
                                                                              \
  u32 openssl_ops_dec_##a (vlib_main_t *vm, vnet_crypto_op_t *ops[],          \
			   u32 n_ops)                                         \
  {                                                                           \
    return openssl_ops_dec_##m (vm, ops, 0, n_ops, b (), iv);                 \
  }                                                                           \
                                                                              \
  static u32 openssl_ops_enc_chained_##a (                                    \
    vlib_main_t *vm, vnet_crypto_op_t *ops[], vnet_crypto_op_chunk_t *chunks, \
    u32 n_ops)                                                                \
  {                                                                           \
    return openssl_ops_enc_##m (vm, ops, chunks, n_ops, b (), iv);            \
  }                                                                           \
                                                                              \
  static u32 openssl_ops_dec_chained_##a (                                    \
    vlib_main_t *vm, vnet_crypto_op_t *ops[], vnet_crypto_op_chunk_t *chunks, \
    u32 n_ops)                                                                \
  {                                                                           \
    return openssl_ops_dec_##m (vm, ops, chunks, n_ops, b (), iv);            \
  }

foreach_openssl_evp_op;
#undef _

#define _(a, b)                                                               \
  static u32 openssl_ops_hash_##a (vlib_main_t *vm, vnet_crypto_op_t *ops[],  \
				   u32 n_ops)                                 \
  {                                                                           \
    return openssl_ops_hash (vm, ops, 0, n_ops, b ());                        \
  }                                                                           \
  static u32 openssl_ops_hash_chained_##a (                                   \
    vlib_main_t *vm, vnet_crypto_op_t *ops[], vnet_crypto_op_chunk_t *chunks, \
    u32 n_ops)                                                                \
  {                                                                           \
    return openssl_ops_hash (vm, ops, chunks, n_ops, b ());                   \
  }

foreach_openssl_hash_op;
#undef _

#define _(a, b) \
static u32 \
openssl_ops_hmac_##a (vlib_main_t * vm, vnet_crypto_op_t * ops[], u32 n_ops) \
{ return openssl_ops_hmac (vm, ops, 0, n_ops, b ()); } \
static u32 \
openssl_ops_hmac_chained_##a (vlib_main_t * vm, vnet_crypto_op_t * ops[], \
    vnet_crypto_op_chunk_t *chunks, u32 n_ops) \
{ return openssl_ops_hmac (vm, ops, chunks, n_ops, b ()); } \

foreach_openssl_hmac_op;
#undef _


clib_error_t *
crypto_openssl_init (vlib_main_t * vm)
{
  vlib_thread_main_t *tm = vlib_get_thread_main ();
  openssl_per_thread_data_t *ptd;
  u8 *seed_data = 0;
  time_t t;
  pid_t pid;

  u32 eidx = vnet_crypto_register_engine (vm, "openssl", 50, "OpenSSL");

#define _(m, a, b, iv)                                                        \
  vnet_crypto_register_ops_handlers (vm, eidx, VNET_CRYPTO_OP_##a##_ENC,      \
				     openssl_ops_enc_##a,                     \
				     openssl_ops_enc_chained_##a);            \
  vnet_crypto_register_ops_handlers (vm, eidx, VNET_CRYPTO_OP_##a##_DEC,      \
				     openssl_ops_dec_##a,                     \
				     openssl_ops_dec_chained_##a);

  foreach_openssl_evp_op;
#undef _

#define _(a, b) \
  vnet_crypto_register_ops_handlers (vm, eidx, VNET_CRYPTO_OP_##a##_HMAC, \
				    openssl_ops_hmac_##a, \
                                    openssl_ops_hmac_chained_##a); \

  foreach_openssl_hmac_op;
#undef _

#define _(a, b)                                                               \
  vnet_crypto_register_ops_handlers (vm, eidx, VNET_CRYPTO_OP_##a##_HASH,     \
				     openssl_ops_hash_##a,                    \
				     openssl_ops_hash_chained_##a);

  foreach_openssl_hash_op;
#undef _

  vec_validate_aligned (per_thread_data, tm->n_vlib_mains - 1,
			CLIB_CACHE_LINE_BYTES);

  vec_foreach (ptd, per_thread_data)
  {
    ptd->evp_cipher_ctx = EVP_CIPHER_CTX_new ();
#if OPENSSL_VERSION_NUMBER >= 0x10100000L
    ptd->hmac_ctx = HMAC_CTX_new ();
    ptd->hash_ctx = EVP_MD_CTX_create ();
#else
    HMAC_CTX_init (&(ptd->_hmac_ctx));
    ptd->hmac_ctx = &ptd->_hmac_ctx;
#endif
  }

  t = time (NULL);
  pid = getpid ();
  vec_add (seed_data, &t, sizeof (t));
  vec_add (seed_data, &pid, sizeof (pid));
  vec_add (seed_data, seed_data, sizeof (seed_data));

  RAND_seed ((const void *) seed_data, vec_len (seed_data));

  vec_free (seed_data);

  return 0;
}

/* *INDENT-OFF* */
VLIB_INIT_FUNCTION (crypto_openssl_init) =
{
  .runs_after = VLIB_INITS ("vnet_crypto_init"),
};
/* *INDENT-ON* */


/* *INDENT-OFF* */
VLIB_PLUGIN_REGISTER () = {
  .version = VPP_BUILD_VER,
  .description = "OpenSSL Crypto Engine",
};
/* *INDENT-ON* */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */